Effects of Insulator Dielectric Passivation Layer on the Breakdown Voltage of AlGaN/GaN High Electron Mobility Transistor

Abstract

Although AIGaN/GaN high electron mobility transistor (HEMT) has been attracted great attention due to its wide bandgap energy of 3.4 eV, high breakdown electric field of 3 MV/em, superior thermal properties, and high electron mobility, very little was repored for the effect of insulator dielectric passivation layer on the breakdown voltage (Vtr) of AIGaN/GaN HEMT. In this paper, we discuss the effect of SiO2;, SiN, Al2O3, HfO2 as an insulator dielectric passivation layer on Vbr AlGaN/GaN FP-HEMIT. The investigation of HEMT was carried out using Technology Computer Aided Design (TCAD). The HEMT with a field plate (FP-HEMT) has a higher Vbr than that of HEMT without a field plate (N-HEMT). The FP-HEMT with HfO2 passivation layer exhibits the highest breakdown vollage of 880 V, The FP-HEMT with SiO2 passivation layer has the lowest breakdown voltage of 175 V. The use of a passivation layer with higher insulator dielectric constant increases the breakdown voltage of HEMT. It is concluded that the AIGaN/GaN HEMT with field plate and passivation layer showed improved performance and reliability.